Tamperproof rotary valve

ABSTRACT

A tamperproof rotary valve which includes a valve body having a fluid flow passage extending therethrough. The passage is intersected by an actuator opening in the body and defining a valve chamber thereat. A rotary valve is disposed in the chamber for opening and closing the fluid flow passage. An actuator is journaled in the actuator opening and is coupled to the rotary valve for rotating the valve. A groove is formed about the actuator, and a contractible/expandable locking ring is disposed in the groove and projects outwardly of the groove beyond the bounds of the actuator when in a free, expanded condition. The locking ring is contractible into the groove to allow assembly of the actuator into the actuator opening. A locking groove is formed in the actuator opening in the valve body and into which the locking ring expands when the actuator is in a proper assembled position in the actuator opening. The actuator has a cam surface for biasing the locking ring into the locking groove in response to any attempted withdrawal movement of the actuator in said opposite direction. A resilient grommet is compressed between an enlarged portion of the actuator and the valve body to generate torque therebetween to resist rotation. A valve seal is disposed in a seal seat in the valve body about the valve ball, the valve seal being resilient and having a stiffening ring embedded therein.

This is a division of application Ser. No. 451,146 filed Dec. 15, 1989.

FIELD OF THE INVENTION

This invention relates to valves and, particularly, to tamperproofvalves such as ball valves, plug valves and the like.

BACKGROUND OF THE INVENTION

Rotary valves of the ball valve or plug valve type are used as gas stopsand for certain other purposes. It is desirable to construct gas stopsso that they cannot be disassembled and reassembled by any unauthorizedperson. Many arrangements have been developed to make tamperproof valvesof the character described. For instance, U.S. Pat. Nos. 2,539,106 toSchenck, dated Jan. 23, 1951; 2,989,081 to Johnson, dated Aug. 4, 1954;and 3,359,999 to Mueller, dated Dec. 26, 1967; all show one form oranother of a valve actuator element which is readily assembled anddifficult if not prevented from being disassembled. This is accomplishedby a snap ring or spring which is inwardly retractable into a groove inthe actuator element during assembly and which is outwardly expandableinto a locking groove in the valve body when fully assembled. A problemwith such constructions is that the snap rings or springs tend to rideout of the locking groove after extended use and wear. Consequently,more positive constructions were developed as shown in Poisker U.S. Pat.No. 3,004,550, dated Oct. 17, 1961.

Most tamperproof gas stops, such as that shown in the Poisker patent,were developed to rely upon the use of some sort of locking arrangementthat requires a special tool to release the valve plug for removal fromthe valve body. In most such instances, the expedience used to make theball or plug valve tamperproof added substantially to its cost.

Accordingly, an improved tamperproof plug valve was developed asdisclosed in U.S. Pat. No. 4,014,512 to Cheever et al, dated Mar. 29,1977 and assigned to the assignee of this invention. That patent shows atamperproof plug valve which requires no special parts other than thevalve body and the valve plug. After the valve plug is inserted into thevalve body, two stacked, slit, frusto-conical, transversely archedspring washers having teeth make a one-way tight friction fit on aprojecting end portion of the valve plug. The outer peripheral portionof the forward of the two washers bears on a recessed planar area of thevalve body which is surrounded by a continuous boss so a prying toolcannot be inserted beneath either washer.

The instant invention provides a rotary valve, shown as a ball valve,wherein the basic means of an expandable locking ring is used forrendering the valve tamperproof but means are provided for preventingthe locking ring from riding out of its locking groove should removal ofthe actuator be attempted.

SUMMARY OF THE INVENTION

An object, therefore, of the invention is to provide a new and improvedtamperproof rotary valve construction of the character described.

In the exemplary embodiment of the invention, generally, the rotaryvalve includes a valve body having a fluid flow passage extendingtherethrough. The passage is intersected by an actuator opening in thebody and defining a valve chamber thereat. A rotary valve is disposed inthe chamber for opening and closing the fluid flow passage in the valvebody. An actuator is journaled in the actuator opening and is coupled tothe rotary valve for rotating the valve.

The invention contemplates providing tamperproof means between theactuator and the valve body including a groove about the actuator, and acontractible/expandable locking ring is disposed in the groove andprojects outwardly of the groove beyond the bounds of the actuator whenin a free expanded condition. The locking ring is contractible into thegroove to allow assembly of the actuator into the actuator opening. Alocking groove is provided in the actuator opening in the valve body andinto which the locking ring expands automatically when the actuator isin its proper assembled position in the actuator opening.

In particular, the locking ring is circular in cross-section and, whendisposed in the locking groove, abuts a surface portion of the groovewhich is of a mating circular configuration. The abutment surfaceportion opposes movement of the locking ring in a direction opposite theinsertion or assembly direction of the actuator into the actuatoropening. Preferably, the depth of the circular locking groove is equalto at least the cross-sectional radius of the circular locking ring. Theactuator itself has a chamfered surface portion facing in a directionopposite the insertion direction of the actuator for preventing thelocking ring from riding out of the locking groove by biasing thelocking ring into the locking groove should any attempt be made toremove the actuator from the actuator opening. In addition, the actuatoropening has a frusto-conical cam surface portion on the lead-in side ofthe locking groove to provide means for engaging and contracting thelocking ring automatically in response to inserting the actuator intothe actuator opening.

Another feature of the invention is the provision of torque generatingmeans between the valve body and the actuator. Specifically, theactuator has an enlarged portion opposing a land portion on the valvebody. These portions are adjacent a tapered mouth between the actuatorand the actuator opening. A resilient grommet has an enlarged headportion for sandwiching between the enlarged portion of the actuator andthe land portion of the valve body, and a tapered portion for biasinginto the tapered mouth between the actuator and the actuator opening.The resilient grommet is compressed upon assembling the actuator intothe actuator opening of the valve body and provides friction resistanceto effect the torque generating means.

A further feature of the invention is an annular resilient valve seal inthe valve body about the fluid flow passage for sealing against thevalve ball. The resilient seal is of a molded structure and has astiffening ring molded integrally therewithin. One side of the resilientvalve seal has a frusto-spherical surface area for engaging the valveball, and the opposite side of the valve seal has a pair of concentricannular ridges projecting therefrom for engaging a generally flatsealing surface on the seal seat of the valve body.

Other objects, features and advantages of the invention will be apparentfrom the following detailed description taken in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of this invention which are believed to be novel are setforth with particularity in the appended claims. The invention, togetherwith its objects and the advantages thereof, may be best understood byreference to the following description taken in conjunction with theaccompanying drawings, in which like reference numerals identify likeelements in the figures and in which:

FIG. 1 is an exploded axial section through the rotary valveincorporating the concepts of the invention;

FIG. 2 is an axial section through the valve in assembled condition;

FIG. 3 is a fragmented section, on an enlarged scale, of the area aboutthe valve actuator which includes the tamperproof means and the torquegenerating means; and

FIG. 4 is a fragmented section, on an enlarged scale, taken radiallythrough the valve seal in the valve body for the valve ball.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The concepts of this invention are exemplified in a rotary valvedisclosed herein in the form of a ball valve illustrated in FIGS. 1 and2. FIG. 1 shows the components of the valve in an exploded depiction,and FIG. 2 shows the valve in fully assembled condition. The ball valveincludes a valve body 10 formed of any suitable material, the precisenature of which is dependent upon the intended use of the valve. Forexample, housing 10 could be formed of plastic, bronze, and the like.Housing 10 has a fluid flow passage 12 extending therethrough toterminate in ports 14 and 16 which are internally threaded to receivefittings (not shown) for intended purposes within a fluid flow line.Fluid flow passage 12 is intersected by an actuator opening 18 in valvebody 10 and defining a valve chamber 20 thereat.

An actuator, generally designated 22, having a lockwing 24, is journaledin actuator opening 18 by means of a depending actuator stem 26. Theactuator stem terminates in a key-type end 28 of rectangularconfiguration.

A spherical valve ball 30 is disposed in valve chamber 20 and includes athrough bore 32 which, as is well known in ball valves, is oriented tobe coaxial with passage 12 to allow fluid to flow therethrough, as shownin FIG. 2. When the valve ball is rotated approximately 90 degrees, bore32 is disaligned with the axis of passage 12 and thus stops fluid flow.To this end, one side of valve ball 30 is provided with a keyway-typegroove 34 for mating with keyed end 28 at the distal end of actuatorstem 26. The dimensions of groove 34 are such that it can slip overkeyed end 28 of the valve stem. The bottom 36 of groove 34 is planar toprovide a positive positional stop for transverse insertion of actuator22 during assembly.

To facilitate assembly of the valve, port 14 actually is formed in afitting 38 which is threaded into an enlarged bore in valve body 10, asat 40. It can be seen that the threaded bore is larger than the diameterof valve chamber 20 and the valve chamber actually opens into theenlarged bore on a diameter, as at 42, which is larger than the diameterof valve ball 30. Therefore, in assembly, ball 30 may be introduced intochamber 20 through enlarged port 40 and area 42, and fitting 38thereafter is threaded into the enlarged bore in the valve body to seatthe valve ball, as described in greater detail hereinafter. A resilientseal ring 44 is compressed between fitting 38 and valve body 10. Fitting38 is retained by the threads and also is made tamperproof by insertinga hardened steel pin 46 into a longitudinally drilled hole 48 at orparallel to the pitch diameter of the threads in the fitting and thevalve body. Actuator 22 is inserted into actuator opening 18 such thatend 28 is parallel to axis 50 before ball 30 is assembled throughenlarged bore 42 into chamber 20 with ball slot 34 parallel to axis 50.In this configuration, through bore 32 of the valve ball is transverseto through passage 12. Lockwing 24 of the actuator then can rotate thevalve ball 90° to its open position wherein the lockwing extends in an"on-line" direction to readily indicate a valve open condition as isconventional in the industry.

The invention contemplates tamperproof means between actuator 22,particularly actuator stem 26, and valve body 10 so that when assembledas described above, the valve cannot be disassembled and reassembled byany unauthorized person. In fact, with the structure of the invention,the valve cannot be disassembled without destroying some of thecomponents thereof.

More particularly, and referring to FIG. 3 in conjunction with FIGS. 1and 2, a groove 52 is machined about valve stem 26 for receiving acontractible/expandable locking ring 54. The locking ring may be ofvarious configurations, including a split, overlapping clip ring whichcan be assembled into groove 52 axially over the end of actuator stem26, or the locking ring may be a C-clip for assembling into groove 52transversely of actuator stem 26. In any event, the locking ring is of adiameter which, when in an expanded condition, projects radiallyoutwardly of groove 52 as shown in FIGS. 1-3. The locking ring issufficiently contractible so as to be contracted totally within thebounds of groove 52 to permit actuator stem 26 to be assembled intoactuator opening 18 in valve body 10 in an insertion direction asindicated by arrow "A" (FIG. 2). The valve body has a locking groove 56(FIGS. 1 and 2) in actuator opening 18 and into which locking ring 54expands automatically when actuator 22 is in its proper assembledposition as shown in FIG. 2.

Locking ring 54 is circular in cross-section to allow for easy assemblyand to prevent the ring from twisting or hanging up during insertion ofthe actuator.

FIG. 3 shows in greater detail the configuration of locking groove 56(FIGS. 1 and 2). Specifically, the locking groove has an upper abutmentsurface portion 56a and a depending tapered portion 56b. As stated,locking ring 54 is circular in cross-section, and circular portion 56aof the locking groove is on a mating radius to that of the locking ring.In addition, the depth of the locking groove is equal to at least theradius of the locking ring, as shown in FIG. 3. As such, locking ring 54is biased toward its expanded condition. To insure positive locking oflocking ring 54 into the locking groove, actuator stem 26 is formed witha chamfered surface portion 58 about the lower edge of groove 52 forengaging the locking ring, as at 60 shown in FIG. 3, the upper edge 59of the groove being precisely square. Therefore, any attempts towithdraw the actuator out of the valve body will cause the chamferedsurface to positively engage against the locking ring and drive thelocking ring into the locking groove in the valve body, particularlyinto circular portion 56a of the locking groove. Tapered portion 56b(FIG. 3) of the locking groove is provided so that a sealing O-ring 62(FIGS. 1 and 2) can easily pass over the locking groove without anyscoring or damage to the O-ring which is fabricated of relatively softresilient material.

Another feature of the invention is the provision of torque generatingmeans between valve body 10 and actuator 22, and the torque generatingmeans again is shown in greater detail in FIG. 3 in conjunction withFIGS. 1 and 2. More particularly, a resilient grommet, generallydesignated 64, is sandwiched between a downwardly facing flat surface 66on an enlargement of actuator 22 and an opposing flat land 68 at the topof valve body 10. Actually, grommet 64 has an enlarged head portion 70which projects radially outwardly and is sandwiched between flat surface66 of the actuator and flat land 68 of the valve body. The grommet alsohas a depending tapered portion 72 which projects downwardly into atapered mouth 74 between actuator stem 26 and the upper area of valvebody 10 in actuator opening 18. As seen in the drawings, this taperedmouth is formed by machining into the valve body at the top of actuatoropening 18.

In comparing FIG. 1 with FIGS. 2 and 3 and particularly with FIG. 3, itcan be seen that when actuator 22 is driven downwardly into assembledcondition in valve body 10, with actuator stem 26 projecting intoactuator opening 18, and when the actuator becomes locked by thedisposition of locking ring 54 in locking groove 56, grommet 64 becomescompressed and engages a number of surfaces, including flat surface 66on the underside of actuator 22, flat land 68 on the top of valve body10, tapered mouth 74 cut into the valve body, and the outsidecylindrical surface of actuator stem 26. This interengagement betweenthe resilient grommet and both the valve body and the actuator providesconsiderable frictional resistance against rotary movement of theactuator relative to the valve body and, thereby, provides torquegenerating means between the valve body and the actuator.

A further feature of the invention is shown in greater detail in FIG. 4in conjunction with FIGS. 1 and 2. Specifically, a pair of ring-likevalve seals, generally designated 80, are disposed in seal seats formedin valve body 10 and fitting 38. During assembly, the right-hand valveseal 80, as viewed in FIGS. 1 and 2, first is disposed in its seatbefore valve ball 30 is assembled into position as described above. Theleft-hand valve seal is disposed in its seat in fitting 38 whereupon thefitting then is threaded into the valve body and the two valve seals 80position and properly seat the valve ball.

The detailed construction of each valve seal 80 is shown best in FIG. 4which is an enlarged, fragmented section radially through the right-handvalve seal as disposed in FIGS. 1 and 2. It should be understood thatboth valve seals 80 are identical in construction but simply arereversed in axial orientation for engaging opposite sides of the valveat the axially spaced junctures between fluid flow passage 12 and valvechamber 20. Specifically, each valve seal 80 is fabricated of resilientrubber-like material 82, the material being dependent upon the fluidbeing handled by the valve, such as to prevent contamination or erosionof the material by the fluid. The valve seal is of a molded constructionand includes a stiffening ring 84 embedded therein during the moldingprocess so as to be molded integrally within the body of resilientmaterial 82. The stiffening ring may be fabricated of metallic materialThe stiffening ring is cup-shaped in cross-section as shown best in FIG.4. The ring stiffens valve seal 80 and prevents pinching and/or clippingof the seal by ball 30 when the ball is throttled under high velocityflow conditions. The cup-shaped stiffening ring also serves as asecondary metal-to-metal seal in event a fire of sufficient intensitydestroys the rubber-like primary seals.

Each valve seal 80 has a frusto-spherical surface area 86 on one sidethereof for engaging valve ball 30. The opposite side of the seal has apair of annular or circular ridges 88 projecting therefrom in an axialdirection opposite the valve ball The ridges engage against a flatsealing surface 90 (FIG. 2) on valve body 10 and a flat sealing surface92 on fitting 38. These ridges are molded integrally with the valve sealand provide high unit load in critical sealing areas and yet provideadequate flexing and a positive seal under all temperature conditions,including low temperatures on the order of -20 degrees F., to allownormal operation of the valve.

It will be understood that the invention may be embodied in otherspecific forms without departing from the spirit or centralcharacteristics thereof. The present examples and embodiments,therefore, are to be considered in all respects as illustrative and notrestrictive, and the invention is not to be limited to the details givenherein.

We claim:
 1. A rotary valve comprising:a valve body having a fluid flowpassage extending therethrough, the passage being intersected by anactuator opening in the body and defining a valve chamber thereat; arotary valve disposed in the chamber for opening and closing the fluidflow passage in the valve body; an actuator journaled in the actuatoropening and coupled to the rotary valve for rotating the valve; andtorque generating means between the valve body and the actuator,including an enlarged portion on the actuator and an opposing landportion on the valve body, a resilient grommet sandwiched between theenlarged portion and the opposing land portion, means defining a taperedmouth between the actuator and the actuator opening adjacent theenlarged portion and the opposing land portion and into which a portionof the resilient grommet is biased in response to properly assemblingthe actuator in the actuator opening.
 2. The rotary valve of claim 1,including locking means for holding the actuator in the actuator openingin a condition for compressing the grommet between the enlarged portionof the actuator and the land portion of the valve body and biasing aportion of the grommet into the tapered mouth.
 3. The rotary valve ofclaim 1 wherein said grommet has an enlarged head portion forsandwiching between the enlarged portion of the actuator and the landportion of the valve body, and a tapered portion for biasing into saidtapered mouth.
 4. A rotary valve comprising:a valve body having a fluidflow passage extending therethrough, the passage being intersected by anactuator opening in the body and defining a valve chamber thereat; arotary valve disposed in the chamber for opening and closing the fluidflow passage in the valve body; an actuator journaled in the actuatoropening and coupled to the rotary valve for rotating the valve; andtorque generating means between the valve body and the actuator,including means defining an inwardly diverging mouth in the actuatoropening, and a resilient grommet member at least in part biased into themouth by a portion of the actuator in response to properly assemblingthe actuator in the actuator opening.
 5. The rotary valve of claim 4wherein at least a portion of the grommet is tapered for positioninginto the diverging mouth.
 6. The rotary valve of claim 5, includinglocking means for holding the actuator in the actuator opening in acondition for compressing the tapered portion of the grommet into thediverging mouth.